Power transmission



C. A. REICHLING POWER TRANSMISSION July 15, 1969 2 Sheets-Sheet 1 Filed NOV. 16, 1967 INVENTOR. CHARLES A. REICHLING fix 0 ATTORNEYS July 15, 1969 c. A. REICHLING 3,

POWER TRANSMISSION Filed Nov. 16, 1967 v 2 Sheets-Sheet 2 m 0 Q\ u.

VENTOR CHARLES A.R HLING BY/ /Z 7 United States Patent 3,455,245 POWER TRANSMISSION Charles A. Reichling. Grosse Pointe Woods, Mich., assignor to Sperry Rand Corporation, Troy, Mich., a corporation of Delaware Filed Nov. 16, 1967, Ser. No. 683.499 Int. Cl. F04b 23/04, 19/00; F04c 1/00 U.S. Cl. 1035 11 Claims ABSTRACT OF THE DISLOSURE A fluid pump or motor having multiple sets of fluid pressure energy translating devices comprising a plurality of rotatable members arranged in side by side relation having pressure responsive differential pressure effective areas for hydraulically holding the rotatable members in continuous abutment with one another during all phases of operation.

Background of the invention This invention relates to power transmission and is particularly applicable to rotary fluid pumps and motors of the sliding vane type. More specifically, this invention pertains to pumps and motors of this general classification wherein the device comprises multiple sets of fluid pressure energy translating devices for providing a pump or motor with an increased volumetric displacement.

Very often a need arises for a pump or motor having a volumetric displacement larger than is ordinarily available.

The prior art discloses several different types of unit construction which employ multiple sets of pumping or motoring elements. These types of units have been commonly referred to as dual or multiple units. Such construction is disclosed in U.S. 2,720,171 issued to F. T. Harrington, et al.; 2,570,411, issued to H. F. Vickers; and 2,401,567, issued to I. F. Jeannin, to name a few. However, in these prior art devices, each set of elements forms a separate pumping or motoring unit. That is, each set of elements is separated from one another by some other element of the device such as a plate or the housing of the device.

While such devices are commonly used in dual or multiple hydraulic systems, they may be used to provide increased volumetric displacement. However, the expense in manufacturing an integrated multiple unit with two or more complete sets of the necessary component parts to provide increased volumetric displacement is economically and competitively impractical, if solely for the purpose of increasing displacement. In addition, the size of such a multiple unit is considerably larger than that of a single unit. Similarly, it is economically and competitively impractical to manufacture a single unit design of increased volumetric displacement which is otherwise unavailable, in that technical difficulties arise in machining the individual parts. That is, it is very diflicult to accurately machine the slots in the rotor of a sliding vane type unit when the width of the rotor is doubled, tripled, or some multiple *width of a single unit. Similar machining difliculties are present in other types of units such as gear pump, etc. The present invention provides a unique and economical pump or motor construction which utilizes conventional sets of commercially available parts which require only minimal modification to increase the volumetric displacement in multiples to a unit size which would otherwise be unavailable. Further, the present invention provides a unit construction with a minimal increase in size and weight for the added volumetric displacement.

3,455,245 Patented July 15, 1969 Summary This invention relates to fluid pumps or motors, and particularly to the sliding vane type comprising substantially identical multiple sets of fluid pressure energy translating devices wherein the rotor members of each device are mounted adjacent one another.

An object of the present invention is to provide a fluid pressure energy translating device with substantially identical multiple sets of pumping or motoring elements to obtain an increased volumetric displacement otherwise unavailable.

Another object of this invention is to provide pressure responsive diflerential pressure effective areas associated with the rotor members for hydraulically holding these members in continuous abutment during operation as a pump or motor.

A further object of this invention is to provide such -a device which is low in cost, with a minimal increase in size and Weight.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings wherein a preferred form of the present invention is clearly shown.

In the drawings FIG. 1 is a sectional view of a preferred form of the present invention taken along line 11 of FIGS. 2 and 3.

FIG. 2 is a section taken on line 2-2 of FIG. 1.

FIG. 3 is a section taken on line 33 of FIG. 1.

Referring now to FIG. 1, there is shown a reversible fluid pump or motor indicated generally by the numeral 10, comprising a three section housing 12, 14, and 1-6 suitably maintained together in fluid sealing relation by bolts 18 and having a cylindrical bore 20 in which is floatably mounted a fluid energy translating device, pump or motor cartridge assembly. This assembly comprises a pair of rotors 22 and 24 each having a plurality of substantially radial slots 26 shown in FIG. 2, in which are slidable vanes 28, the outer tips of which are urged by springs 30 against the inner periphery 32 and 34 of a pair of vane track cam ring members 36 and 38 respectively, and two cheek plates 40 and 42 on opposite sides of the cam ring members 36 and 38 and rotors 22 and 24. A cam ring, and a rotor with vanes constitutes a set of pumping or motoring elements. However, it should be understood that a single ring can be used in combination with two or more rotors, in which case, a rotor with vanes and the ring would constitute a set of pumping or motoring elements.

Two bolts 44 and two dowels 46 extend through the check plate 42, ring members 36 and 38, and cheek plate 40 for the purpose of axially holding the rings, rotors and cheek plates firmly together as a cartridge unit assembly, and to prevent relative rotation of the cheek plates and rings. The bolts 44 .are shown in FIGS. 1, 2, and 3, however, the dowels 46 are only shown in FIGS. 2 and 3. The length of the dowels 40, though not shown in FIG. 1, is approximately the same length as the bolts 44. The cartridge assembly is prevented from rotating in the 'bore 20 by means of a dowel pin 48 fitted in the housing 12 and cheek plate 40, however, the cartridge assembly is provided with slight axial movement within the bore 20, between the housing sections 12 and 16.

The rotors 22 and 24 are drivingly engaged with a shaft 50 by means of a spline connection 51. The shaft has male splines indicated by the numerals 52 and 54 which are in alignment with one another. The shaft is supported within the housing at one end by a bearing 56 located in the housing section 16 and at its opposite end by a bearing 58 located in the cheek plate 40. The male splines 52 and 54 on a shaft 50 fit a female spline 55 in each of the rotors 22 and 24, respectively, with a small clearance so that a slight amount of play is provided radially and longitudinally for the rotors to take up a position in proper relationship with other elements of the cartridge assembly. The splines of the shaft 52 and 54 are provided with a specified number of teeth, one of which is identified in a suitable manner as the matching tooth. Similarly, the splines 55 in each rotor are provided with the same pitch diameter and number of teeth as the splines on the shaft and have a specific relationship with respect to the vane slots. A pair of adjoining teeth on each rotor is identically identified with re spect to a particular vane slot on each rotor between which the male spline matching tooth is to engage. Assembly of the rotors onto the shaft in conformity to this tooth identification assures proper alignment of the rotor vane slots 26 of each rotor with one another. That is, all the rotor vane slots in rotor 22 will be aligned with all the rotor vane slots in rotor 24. This is necessitated to achieve proper unit operation and maximum efliciency. A shaft seal 60 is provided preventing leakage between the shaft 50 and housing 16..

The cheek plates 40 and 42 are provided respectively with plane inner surfaces 62 and 64 which are adapted to be urged into proper sealing engagement and relation with the outer plane surfaces 66 and 68 of the ring members 36 and 38 and with the outer plane surfaces 70 and 72 of the rotors 22 and 24, respectively. The combined width of the ring members 36 and 38 is slightly greater than the combined width of the rotors 22 and 24 to provide proper running clearance between the inner faces of the cheek plates and the outer surfaces of the rotors. This running clearance is maintained substantially equal to that of a unit having a single set of pumping or motoring elements. This is accomplished by providing one ring and rotor having the regular or ordinary side clearance and another ring with a width substantially equal to its corresponding rotor. The cheek plates are adapted to deflect slightly to reduce the running clearance during operation as is fully described in Patent No. 3,204,565, issued to K. V. Kirkpatrick on Sept. 7, 1965. Two pairs of diametrically opposed fluid zones 74 and 76, and 78 and 80, as shown in FIG. 2, are formed in the space between the outer circular periphery of the rotors 22 and 24, and the elliptical shaped inner periphery of the rings 36 and 38 and through which the vanes sweep with their outer tips thereof in engagement with the elliptical vane track. Either pair of fluid zones may be fluid inlet zones while the other pair of fluid zones are fluid outlet zones, depending upon the mode and directional operation of the device.

Each vane is provided with a plurality of stepped passages 82 having chamfered openings 84 at the tip of the vane and within the enlarged portions of the passages are placed the springs 30. As the tip of each vane sweeps through the fluid zones of the device, the pressure existing at the outer ends is transmitted to the inner chamber 86 of each vane slot by means of the vane passages 82 for the purpose of pressure balancing the vane. The outwardly urging force to maintain the tips of the vanes in contact with the vane track is provided by centrifugal force and the springs 30.

The cartridge assembly is floatably mounted in the bore 20 for slight axial movement between axial abutments 88 and 90 and forms and defines two chambers 92 and 94 within the bore 20 at opposite sides of the cartridge assembly, either of which is adapted to be an inlet chamber while the other is an outlet chamber. The detailed construction of the cheek plates and their association with the housing 12 and 16 and, as aforementioned, for accomplishing deflection of the cheek plates to reduce the running clearance between the cheek plates and the side of the rotors is fully explained in the above-mentioned Kirkpatrick patent. The extreme end faces 98 and 100 of the cartridge assembly are exposed to low pressure by reason 4 of chambers 102 and 104 being connected through a shaft bleed passage 106 and a pair of transverse passages 107 to a bleed port 109 formed in housing section 12.

For the purpose of making the device inherently reversible without the use of special valving, two flow passages opening to the exterior of the housing are independently connected to the chambers 92 and 94 and porting is provided in each check plate for independently connecting one of the chambers to one pair of fluid zones and the other chamber to the other pair of fluid zones. Thus, a flow passage 108 is provided in housing section 16 connected directly to chamber 94 and having an external opening connection 114. Cheek plate 42 is provided with a pair of ports 116 and 118 (shown in dotted lies in FIG. 2) formed by cutting away portions of the cheek plate 42 extending from the outer periphery of the plate, which ports are displaced 180 from each other, and which extend completely through the cheek plate 42. The ports 116 and 118 are adapted to connect chamber 94 to the pair of diametrically opposed fluid zones indicated by the numerals 78 and shown in FIG. 2. Cheek plate 40 is provided with a duplicate set of diametrically opposed cutaway ports 120 and 122 also displaced 180 from each other but displaced apart from the duplicate ports 116 and 118 in cheek plate 42. The other ports and 122 directly connect the chamber 92 respectively to the other pair of diametrically opposed fluid zones indicated by the numerals 76, and 74 in FIG. 2. Either of the flow passages 108 or 112 and either of the chambers 94 and 92 may be an inlet flow passage or an inlet flow chamber, respectively, while the other flow passage and chamber are respectively performing the function of an outlet passage and an outlet chamher.

The cheek plate 40 is provided with a pair of diametrically opposed cutaway ports 116 and 118, respectively, in cheek plate 42, and the cheek plate 42 is provided with a pair of diametrically opposed, recessed ports 128 and 130 axially opposed to the cutaway ports 122 and 120, respectively, in cheek plate 40. In addition, the ring members 36 and 38 are provided with two pairs of diametrically opposed ports extending completely through the ring member, one pair of which, indicated by the numerals 132 and 134, connect the cutaway port 116 in cheek plate 42 with the recessed port 124 in cheek plate 40, and the other pair of which, indicated by the numerals 136 and 138, connect the cutaway port 118 in cheek plate 42 to the recessed port 126 in cheek plate 40.

The ring members 36 and 38 are also provided with two other pairs of diametrically opposed ports also extending through the ring, one pair of which, indicated by the numerals 140 and 142, connects cutaway port 122 in cheek plate 40' to the recessed port 128 in cheek plate 42 while the other pair of ports, indicated by the numerals 144 and 146 connects the cutaway port 120 in cheek plate 40 to the recessed port 130 in cheek plate 42.

In addition to the passages 82 in each vane 28, utilized for pressure balancing purposes, auxiliary porting is provided in each cheek plate for connecting whichever are the high pressure and low pressure sides of the device to the inner chambers 86 of each vane slot in phase with the outer ends of the vanes passing through the high and low pressure fluid zones of the device. Referring to FIG. 3, cheek plate 40 is provided with four recessed ports on its inner face which are spaced in 90 relationship and adapted to register with the inner chambers 86 of the vane slots as the rotor turns, the ports being indicated by the numerals 148, 150, 152, and 154. Port 148 is connected to the cutaway port 120 by intersecting passages 156 and 158; port is connected to recessed port 124 by intersecting passages 162 and 164; port 152 is connected to cutaway port 122 by intersecting passages 166 and 168; and port 154 is connected to recessed port 126 by intersecting passages 170 and 172. Check plate 42 is provided with duplicate sets of ports and passages identical with those provided for cheek plate 42, only two of which are shown in FIG. 1.

Counter bores 174 and 176 are provided on the inner surfaces 62 and 64 of cheek plates 40 and 42, respectively. The counter bores 174 and 176 alternatively could be provided in the outer surfaces of the rotors 70 and 72, respectively. An additional counter bore 178 is provided on the abutting surface 180 of the rotor 24. The counter bore 178 could be alternatively provided on the surface 181 of rotor 22, or in both. The counter bore 178 is slightly larger in diameter than the counter bores 174 and 176 in the cheek plates, as shown in FIG. 2, for purposes to be described hereinafter in the operation.

In operation, if the device is operated as a motor and if the fluid under pressure is directed to external connection port 110 of housing section 16, the chamber 108 will be the high pressure chamber of the device while the chamber 112 and 92 will be under low pressure. Pressure fluid conducted to chamber 108 is conducted to fluid zones 78 and 80 by cutaway ports 116 and 188 of cheek plate 42, acting an fluid inlet ports, the pressure fluid acting on the vanes to turn the rotor and thus the shaft. Fluid displaced from the outlet zones 74 and 76 is conducted by cutaway ports 122 and 120 in cheek plate 40' to chamber 92 by means of passage 112 to the external connection outlet port 114.

As the vanes sweep through the high pressure fluid zones 78 and 80, the fluid pressure under the vanes in chambers 86 is similarly under high pressure. Since the radial surface area between the outer periphery of the rotor and chamber 86 on the side surfaces are equal and subject to the same fluid pressure, the resulting hydraulic force acting on these radial surface areas will be equal and therefore balance one another. However, since the counter bores 174, 176, and 178 are at low pressure, there will exist a pressure gradient across the surfaces of the rotor between the chambers 86 and these counterbores due to the leakage of the fluid across these surfaces, The radial surface areas between the chambers 86 and these dial surface areas between the chambers 86 and these counterbores constitute pressure effective areas upon which the pressure gradient acts to establish hydraulic forces on the rotor. Since there is a difference in the diameter of the counterbores 174 and 176, and the diameter of the counterbore 178, a differential pressure effective area is established. This differential pressure effective area is shown in FIG. 2 as the radial surface area between the diameter of counterbore 178 and the smaller diameter of the counterbore 176 shown by the dotted lines. As a result of this differential pressure effective area, the hydraulic force acting on the outer surfaces 70 and 72 of the rotors 22 and 24 respectively, is greater than the hydraulic force on the inner surfaces 181 and 180 of rotors 22 and 24, respectively. Thus, the rotors 22 and 24 will be hydraulically held in abutment and function as a single rotor during all phases of operation. It should be understood that the entire radial surface between the counterbores 174 and 176 and 178 do not constitute the differential pressure effective area, but only that segment of this radial surface across which leakage will flow from the chambers 86 that are under high pressure to the respective counterbores which are at low pressure. For example, in the unit herein described, approximately one half the radial surface area between counterbores 174, 176 and 178 will be subject to a pressure gradient, while substantially one half will not. This is due to the fact that substantially one half of the chambers 86 are subject to high pressure, while the other half of the chambers 86 are under low pressure. Since the area of the pressure effective area subject to the pressure gradient for each rotor is the same, the exact amount of area which constitutes the pressure effective area is immaterial, so long as a sufficient pressure effective area exists to hydraulically force the rotors together and maintain the rotors in abutment during all phases of operation.

The differential pressure effective areas will be unchanged if the counterbores 17 4 and 17 6 are alternatively placed in the outer surfaces 7 0 and 72 of the rotors 22 and 24 and the counter bore 178 is placed on the inner surface 181 of rotor 22. The actual placement of these counterbores in the alternative surfaces is immaterial so long as the proper differential pressure effective area is achieved. Thus, the multiple rotors function in the same manner as that of a single rotor.

Thus, the rotors will function in a similar manner as a unit having a single rotor, as shown in the Kirkpatrick patent previously noted, in that the rotors will be hydraulically held in a central position between the two cheek plates. That is, the hydraulic force on each side of the rotors, due to the leakage across the sides of the rotors is equal, thereby positioning the rotors equally distant from each cheek plate.

Similarly, when the unit is operated either in the reverse direction as a mot-or or as a pump in either direction, the same hydraulic force unbalance is achieved on the rotors. The only difference being the location of high and low pressure fluid zones.

It should thus be apparent from the foregoing description that the invention provides a unique arrangement for increasing the placement of a fluid pump or motor to a size otherwise unavailable through the use of multiple rotors. It should further be seen that the rotors will be hydraulically held together and remain in continuous abutment during all phases of operation. Since only minimum modifications to commercially available parts are needed, the cost to manufacture such a device will be minimal. Also, since the rotors are placed adjacent one another, the size of the device remains compact.

While the form of embodiment of the present invention as herein disclosed constitutes a preferred form, it is to be understood that other forms might also be adapted, all coming within the scope of the claims which follow.

What is claimed is as follows:

1. A fluid pump or motor comprising: multiple sets of fluid pressure energy translating devices having relatively rotatable members; and pressure responsive differential pressure effective surface areas associated with said rotatable members for holding said rotatable members in abutment with one another.

2. A fluid pump or motor comprising: a housing; multiple sets of fluid pressure energy translating devices within said housing and including rotatable members in sideby-side relation; and pressure responsive differential pressure effective surface areas associated with said rotatable members oriented for hydraulically maintaining said members in abutment with one another.

3. A fluid pump or motor comprising: a housing having a longitudinal bore closed at each end by side members; multiple sets of fluid pressure translating devices arranged within said bore and between said side members, and said devices having rotatable members forming high and low fluid pressure zones at their periphery between said side members, said rotatable members having outer surfaces immediately adjacent said side members and inner surfaces immediately adjacent one another, said outer and inner surfaces having pressure effective areas connected to said high pressure fluid zone and said pressure effective area on each of said outer surfaces being larger than said pressure effective area on each of said inner surfaces whereby said rotatable members are urged toward one another for maintaining said inner surfaces of said rotatable members in abutment with each other.

4. The combination, as defined in claim 3, wherein one of said inner surfaces of said rotatable members has a recess forming a cavity which is connected to low pressure.

5. The combination, as defined in claim 3, wherein one of said inner surfaces of said rotatable members has a circular recess forming a cavity which is connected to low pressure; and each of said outer surfaces of said rotatable members has a circular recess forming a cavity exposed to low pressure and having a diameter smaller than said recess in said inner surface.

6. A fluid pump or motor of the sliding vane type comprising: a housing; a plurality of rotor members arranged in side-by-side relation Within said housing; and pressure responsive differential pressure effective surface areas as sociated with said rotor members for hydraulically holding said rotor members in abutment with one another.

7. A fluid pump or motor of the sliding vane type comprising: a housing having a bore therein; a fluid pressure energy translating cartridge arranged in said bore, said cartridge comprising: a ring member; side plates on either side of said ring member and in abutment therewith; a plurality of rotor members arranged within said ring member and having a combined Width slightly less than the width of said ring member, said rotor members having radial slots the full width of said rotors; vanes slidable in said slots forming high and low fluid pressure Zones between said rotor members and said ring member; first pressure effective areas arranged on the surfaces of said rotor members adjacent said side plates and second pressure effective areas arranged on the surfaces of said rotor members adjacent one another, said first pressure effective areas being larger than said second pressure effective areas, thereby providing a differential pressure effective area between said outer and inner surfaces of said rotor members for hydraulically holding said inner surfaces of said rotor members in abutment with one another.

8. The combination, as defined in claim 7, wherein said ring member comprises a plurality of ring members, the combined width of which is slightly greater than the combined width of said rotor members.

9. The combination, as defined in claim 7, wherein said ring member comprises a plurality of ring members equal in number to said rotor members, the combined width of which is slightly greater than the combined width of said rotor members.

10. The combination, as defined in claim 7, wherein one of said inner surfaces having said second pressure effective areas has a circular recess forming a cavity connected to low pressure.

11. The combination, as defined in claim 10 wherein each of said surfaces having said first pressure effective areas has a circular recess forming a cavity connected to low pressure, but which is smaller in diameter than said recess in said second pressure effective surface area on said inner surface of said rotor member.

References Cited UNITED STATES PATENTS 2,720,171 10/1955 Harrington et a1.

2,845,873 8/1958 Lapsley 230-158 X 3,204,565 9/1965 Kirkpatrick 103136 3,204,566 9/ 1965 Feroy.

3,246,574 4/1966 Eickmann 103-136 X 3,334,591 8/1967 Dymond 103-136 3,344,745 10/1967 Scognarnillo 230158 X 3,352,290 11/1967 Kuroda 230-158 X DONLEY J. STOCKING, Primary Examiner WARREN J. KRAUSS, Assistant Examiner US. Cl. X.R. 103-426, 136; 230158 

